METHOD AND APPARATUS FOR ADAPTING THE SPEED OR PITCH OF REPLAYED OR RECEIVED DIGITAL AUDIO SIGNALS HAVING A GIVEN SPEED OR PITCH, OR FOR MARKING DIGITALLY ENCODED AUDIO SIGNALS HAVING A GIVEN SPEED OR PITCH

摘要

The major TV systems in the world use interlaced scanning and either 50Hz field frequency or 60Hz field frequency. However, movies are produced in 24Hz frame frequency and progressive scanning, which format will be used for future digital video discs to be sold in 50Hz countries. In 50Hz display devices the disc content is normally presented with increased A/V signal speed and thereby increased audio pitch. Parts of the audio signal or signals are dropped, or are inserted or repeated, in order to achieve upon reproduction on average the original audio source signal pitch, and to enable audio output via a standardised digital audio interface. The insertion/repeat or dropping is controlled by a corresponding marking information signal which can be generated automatically at encoder or at decoder side, or by an operator at encoder side.